The present invention is directed towards boat hulls, and in particular boat hulls having three sponsons.
Tunnel hull boat structures having a pair of longitudinal side channels that define a central tunnel in which is located a central sponson are known. Such boat hulls are typically configured so that the outer sponsons and central sponsons collectively sit in the water at low speed, however at higher planing speeds, the boat hull is partially supported by the surfaces of the side sponsons planing on the water and partially by air being compressed between the inside surfaces of the outer sponsons, the tunnel roof and the water surface.
Conventional tri-sponson boat design lacks versatility in that the designs are generally intended to be used in smaller pleasure-boat type applications and do not lend themselves well to being scaled to larger boats. Conventional designs also tend to lack versatility in that while a particular design maybe suitable for use in a specific environments, the same design may not be suitable for use in other environments. For example, a tri-sponson boat structure which may be quite efficient in smooth water conditions may not be suitable for rougher waters and a tri-sponson design intended for rougher waters may be inefficient in smoother waters.
Accordingly, there is a need for a tri-sponson boat hull that is scalable, and which can provide a smooth, efficient ride over a range of speeds and water conditions. There is also a need for an efficient method for manufacturing such a boat hull.
According to one aspect of the present invention there is provided a boat hull that includes an upper hull section, a pair of spaced apart substantially parallel elongated outer sponsons extending from a forward portion to a stern portion of a bottom of the upper hull section, the outer sponsons and upper hull section defining a tunnel therebetween, and an elongated center sponson extending along the bottom of the upper hull and positioned in the tunnel between and substantially parallel to the pair of outer sponsons and having a forward section with an upwardly extending trailing step wall defining an upward step in the center sponson, and an aft section that is located aft of the forward section, the aft section having an upwardly curved leading edge intersecting the step wall of the forward section.
According to another aspect of the invention, there is provided a boat hull that includes an upper hull section, a pair of spaced apart substantially parallel elongated outer sponsons extending from a forward portion to a stern portion of a bottom of the upper hull section, the outer sponsons and upper hull section defining a tunnel therebetween, the outer sponsons each having an inner wall extending substantially perpendicular to a water line, an outer chine and a bottom wall joining, bottom edges of the inner wall and the outer chine, the bottom wall being substantially planar aft of a leading edge thereof and angled upwardly from the inner wall to the outer chine, the upward angle of the bottom wall relative to the water line being less than that of the outer chine, and an elongated center sponson extending along the bottom of the upper hull and positioned in the tunnel between and substantially parallel to the pair of outer sponsons, the center sponson extending forwardly of the outer sponsons and having a upward step along its length with a portion of the center sponson leading the step having a greater depth than a portion of the center portion aft of the step, the center sponson being of lesser depth than the outer sponsons.
According to another aspect of the invention, there is provided a boat hull that includes an upper hull section having a substantially planar underbody, a pair of spaced apart substantially parallel elongated outer sponsons extending from a forward portion to a stern portion of the underbody of the upper hull section, the outer sponsons and underbody defining a tunnel therebetween, and an elongated center sponson extending along the underbody and positioned in the tunnel between and substantially parallel to the pair of outer sponsons.
According to still another aspect of the invention, there is provided a boat hull having an upper hull section, a pair of spaced apart substantially parallel elongated outer sponsons extending from a forward portion to a stern portion of a bottom of the upper hull section, the outer sponsons and upper hull section defining a tunnel therebetween, and an elongated center sponson extending along the bottom of the upper hull section and positioned in the tunnel between and substantially parallel to the pair of outer sponsons, the center sponson extending further forward and aft-ward than the outer sponsons.
According to yet another aspect of the invention, there is provided a boat hull having a bow and a stern, the hull comprising an upper hull section, a pair of spaced apart substantially parallel elongated outer sponsons extending from a forward portion to a stern portion of a bottom of the upper hull section, the outer sponsons and upper hull section defining a tunnel therebetween, an elongated center sponson extending along the bottom of the upper hull section and positioned in the tunnel between and substantially parallel to the pair of outer sponsons, and a wing-shaped lift spoiler pivotally mounted between the pair of outer sponsons, the spoiler passing beneath an aft section of the center sponson and being adjustable to control trim of the boat hull during use.
According to another aspect of the invention there is provided a method of making a tri-sponson boat hull, including steps of (a) forming from reinforced fibre material, using an upper hull mold, an upper hull section having a substantially planar underbody; (b) forming from reinforced fibre material, using first and second outer sponson molds, an elongated first outer sponson and an elongated second outer sponson; (c) forming from reinforced fibre material, using a center sponson mold, an elongated center sponson; (d) arranging the upper hull section, first and second outer sponsons and the center sponson such that the first and second outer sponsons extend from a forward section to a stern portion of the underbody of the upper hull section, the outer sponsons and underbody defining a tunnel therebetween, and the center sponson extends along the underbody of the upper hull and is positioned in the tunnel between and substantially parallel to the first and second outer sponsons; and (e) securing the outer sponsons and center sponson to the upper hull using reinforced fibre material.
According to yet another aspect of the invention there is provided a method of making a boat hull that includes steps of layering up on a boat hull mold blended Kevlar (T(trademark)) and E-glass woven fabrics that are pre-impregnated with heat curable epoxy resin, and heat curing the layered fabrics.